The objectives of this study are to obtain information about the permeability, fine structure, and basal lamina of regenerating capillaries in skeletal muscle wounds of normal and vitamin C deficient animals. Particular attention will be paid to: 1) the permeability of regenerating capillaries as determined by assaying the time and quantity of isotopically labeled plasma escaping from capillaries in normal and scorbutic animal skeletal muscle wound preparations; 2) the ultrastructural characterization of the growing capillaries in scorbutic animal wounds; 3) the elucidation of fine structural detail and suggested composition of the capillary basal lamina as shown by the ultrastructural, electron histochemical stains, and permeability studies; 4) localization and identification of broad groups of acid mucopolysaccharides in the connective tissue of healing wounds; 5) localization and determination of cell or cells or origin of capillary basal lamina by employing isotopes and electron microscopic autoradiography; and, 6) the correlation of ultrastructural and permeability data in order to verify or challenge current theories of growing capillaries and their transcapillary exchange. If the objectives of this study are fulfilled, then a significant step can be made toward correlating permeability function with morphological fine structure of the microcirculation of healing wounds.